6^ DOCTRINE OP MIXED CASES. 



lify this fo as to make the comparifon more fair, by determin- 

 ing the fpccific heat of folid wax and fpermaceti ; but I have 

 not been able to fatisfy myfelf with either of thefe points, 

 owing to the foftnefs and confequent abforption of latent heat, 

 which a very low degree of heat inducer in both thefe bodies. 

 The numbers expreffing their latent heats are therefore too 

 low. On infpedion of the above table, there does not appear 

 any ratio by which the quantity of the caloric of fluidity feems 

 to be guided : it certainly does not increafe with the difficulty 

 of fufion, but moft probably has fome connexion with the re- 

 lative capacity of each body in its folid and fluid ftate. The 

 determination, however, of the capacity of any of the metals 

 in a fluid form, excepting meroury, muft be regarded as an 

 extremely difficult talk. 



XL 



StriBures on Mr. Dalton's Do6irinc of Mixed Gafes, and an 

 Anfwer to A/r. Henry's Defence of the fame. In a letter 

 from Mr. John Gough. 



To Mr. NICHOLSON, 

 SIR,. 



Ciufes of thefe X H A V E ventured to defend the chemical union of water and air, 

 ftnCtures. ^^ y^,gij ^^ ^j^g homogenity of the atmofpherical gas. My thoughts 



on thefe fubjefts are briefly ftated in your Journal ^ ; and the 

 farther profecution of the enquiry compels me to make an open 

 attack on my friend Mr. Dalton, and his new convert, Mr. 

 Henry. The difpule fliall be fairly conduced on my part ; 

 that is, it fliall confift of arguments which I am ready to aban- 

 don as foon as they are refuted ; tliis promife is due to friend- 

 fliip, as well as the obligations of truth. 

 Dalton'8 a hypo- The firft thing to be afcertained is the proper appellation of 

 thefis not a the- ^fp. Dallon's opinions. His dodrine of mixed gafes is offered 

 to the public as a mechanical theory, founded on chemical 

 fa6ls : a little attention, however, to Mr. Dalton 's etfays, will 

 deprive it of all claim to the title of a theory. This is evident 

 from the nature of the mechanical philofophy ; every branch 



* Vol. Vin. Page 243, 



of 



